Use ROCm5.3 branch for MIOpen

[jithunnair-amd]

Using -eq instead of -ge seems more appropriate since we don't intend to use older MIOpen branches for newer ROCm releases anyway.

[jataylo]

@jithunnair-amd pytorch#1169

Should we revert to -ge to support the 5.1.1 case? Otherwise the [build-docker-rocm (5.1.1)] job in upstream CI fails

pytorch#67 1.099 + [[ 50101 -eq 50300 ]]
pytorch#67 1.099 + [[ 50101 -eq 50200 ]]
pytorch#67 1.099 + [[ 50101 -eq 50100 ]]
pytorch#67 1.099 + [[ 50101 -eq 50000 ]]
pytorch#67 1.099 + [[ 50101 -eq 40500 ]]
pytorch#67 1.099 + [[ 50101 -eq 40300 ]]
pytorch#67 1.099 + [[ 50101 -eq 40200 ]]
pytorch#67 1.099 Unhandled ROCM_VERSION 5.1.1
pytorch#67 1.099 + echo 'Unhandled ROCM_VERSION 5.1.1'
pytorch#67 1.099 + exit 1
pytorch#67 ERROR: executor failed running [/bin/sh -c bash ./install_miopen.sh ${ROCM_VERSION} && rm install_miopen.sh]: exit code: 1
rocm_final 9/11] RUN bash ./install_miopen.sh 5.1.1 && rm install_miopen.sh:
executor failed running [/bin/sh -c bash ./install_miopen.sh ${ROCM_VERSION} && rm install_miopen.sh]: exit code: 1